Methods and machines for forming cartons



Nov. 28, 1967 R. J. HlcKlN METHODS AND MACHINES FOR FORMING CARTONS Filed Feb. 18, 1965 l 7 Sheets-Sheet 1 I 'Il' l l l l lv ,l I l R. J. HlcKlN 3,354,797

METHODS AND MACHINES FOR FORMING CARTONS Nov. 28, 1967 7 Sheets-Sheet 2 Filed Feb. 18, 1965 NN v on@ Naw Nov. 28, i967 R. J. HlcKlN METHODS A-ND MACHINES FOR FORMING CARTONS www mm w 6% wma Q sw N5 eww Filed Feb. 18, 1965 Q www Nov. 28, 1967 R. 1. HICKIN 3,354,797

METHODS AND MACHINES FOR FORMING CARTQNS F`iled`F`eb. 18, 1965 7 Sheets-Sheet 4 1 @www f a W ,wlw w, ,W 9b m u k EE: www .Tolk wwN om xtwbxwxo; toxkv M w \NW 9%. TWM n I I I I I I l I I nl' v A JHHHHHHH. 5 f ma IV 0 wmiisni@ u y Qu -eS N i w@ MII. s Om\ N\\ NW N WN d@ Bix, Nw 5&5 i 5 5 Nov. 28, 1967 R. 1. HlcKlN 3,354,797

METHODS AND MACHINES FOR FORMING CARTONS Filed Feb. 18, 1965 7 Sheets-Sheet 5 Nov. 28, 1967 R. J. HxcKlN 3,354,797

METHODS AND MACHINES FOR FORMING CRTONS .7 Sheets-Sheet 6 Filed Feb. 18, 1965 CaronA/ove/m /gg Y Y '1 mf /a 62 ./64 Si? @s Nov. 28, 1967 R. J. HlcKlN METHODS AND MACHINES FOR FORMING CARTONS '7 Sheets-Sheet 7 Filed Feb. 18, 1965 NN 0 wwvm VNS United States Patent O 3,354,797 METHODS AND MACHHNES FR FORMTG CARTNS Robert I. Hickin, Seville, Ohio, assignor, by mesne assignments, to Packaging Corporation of America, a corporation of Delaware Filed Feb. 1S, 1965, Ser. No. 433,715 15 Claims. (Cl. 93--49) ABSTRACT F THE DSCLSURE A conveyor having opposed sets of folder plates for folding bellows-fold gussets at the corners of erected tubular carton blanks, carries the blanks through a folding station where spreaders are extended laterally of the conveyor into the open ends of the cartons and spread the top and bottom end liaps. Thereupon, the folders begin folding the gusset flaps inward, the spreaders retract, and the folders complete their inward folding movement. Y- shaped tuckers subsequently move inward against the upper portion of the respective gussets to assist in completion of the gusset folds. The folders are reversible and include adjustable members for effectively folding panels of various Widths.

This invention pertains to methods and machines for forming cartons and particularly pertains to improvements on the methods and machines disclosed in the copending application Ser. No. 399,778 of Edwin l. Plough filed Sept. 28, 1964, now Patent No. 3,309,969 issued Mar. 21, 1967, for forming cartons having bellows-type, infolded gussets at their corners.

Carton constructions have long been known wherein a tubular blank is provided with gussets at each of the four corners and these gussets are pushed inward during the final erection and closing of the carton to form a carton having an octagonal inner compartment. These cartons are particularly adapted for packaging disc-shaped articles such as pies. Many products of this type are produced in large quantities at a high production rate, on an assembly line basis, thereby requiring rapid packaging operations.' While certain conventional packaging steps in the erection, filling and closing of these cartons may be performed with previously known machines, the gusset-folding 4step was not successfully automated prior to the advent of the improvements disclosed and described -in the above-noted application.

The specific example of a machine shown and described in the Plough application utilizes pairs of fixed cam bars, or spreader bars, to insure that the end portions of the top and bottom walls of the blank buckle outwardly of one another as the gussets are pressed between these walls to their in-folded positions. However, it has been found that static devices, such as fixed spreader bars, do not readily lend themselves to the rapid changes which must be effected in spreading the ends of a carton to fold the gussets, particularly in high rate of production, cartoning line operations. Accordingly, it is one object of this invention to prov-ide improved means for insuring spreading of the carton ends in machines of this type.

It has been found that gussets can be readily and successfully folded by machines if the gusset folders are of a width slightly less than the thickness or depth of the carton, i.e., the width of the gussets being folded. If the width of the gusset folders are a great deal less than the thickness of the cartons, the gussets do not fold properly However, considerable down-time and attendant loss of production is encountered if it is necessary to change folders with each change to gusseted cartons of different Mice depth. Accordingly, it is another object of this invention to provide improved machines to handle cartons of a wide range of depth Without requiring a change in width of the gusset flap folders.

It is another object of this invention to provide improved methods and machines for use in rapidly and mechanically forming and closing cartons having gussets in one or more walls thereof.

It is another object of this invention to provide improved methods and machines to facilitate efficient forming and closing of cartons having gusseted corners, and particularly to provide such methods and machines for cooperation with other known carton-ing mechanism for automatically forming and closing cartons having corner gussets.

It is another object of this invention to provide mechanisms for positively and effectively spreading the end portions of tubular carton blanks in cartoning machines, and particularly in such machines where the cartons are carried through the machine on continuous motion conveyors.

It is another obje-ct of this invention to provide improved methods and machines for automatically closing and forming cartons having corner gussets, and which are readily adaptable for forming such cartons from blanks of various depths.

It is another object of this invention to provide improved folders for use in cartoning machines for forming and closing cartons having corne-r gussets.

Further additional objects and advantages of this invention will become apparent to those skilled in the art from the following description, the accompanying drawings andthe appended claims.

In carrying out this invention in one illustrative form, a tubular carton blank having bellows-fold gussets at the four corners is supported in squared-up condition on a moving conveyor. Spreader means are provided at each side of the conveyor comprising movable elements which enter each end of the carton blank and are actuated to spread the top and bottom walls of the respective ends as such carton is carried by said conveyor. Folders carried by said conveyor then push the gussets inward, and the spreader means retract, whereupon the folders continue their inward movement to the final Vinfolded gusset position. A tucker member engages each end of each carton blank adjacent the top wall to insure complete accurate folding of the gussets. The conveyor then carries the resulting partially erected blank between pressers which press the top and bottom walls toward one another to retain the gussets in 4folded position. Thereafter suitable end flaps on the blank may be closed and secured, or other retaining means applied, in a conventional manner and by any suitable means to retain the carton .in the resulting erected state and to complete the carton.

For a more complete understanding of this invention reference should now be had to the example illustrated in the drawings, wherein:

FIG. l is a fragmentary top plan View of a portion of a carton-forming machine including mechanism embodying teachings of this invention, and with a series of carton blanks thereon, the top lportions of one of the blanks being broken away;

FIG. 2 is a side elevation view of the mechanism of FIG. l;

FIG. 3 is a fragmentary perspective view of the mechanism of FIG. l with certain of the carton blanks removed;

FIG. 4 is an enlarged partial perspective View of a completed carton with gusseted corners;

FIGS. 5 and 6 are fragmentary side perspective views of the mechanism of FIG. 1, taken from the right side of FIG. 3 and with the operative mechanism in different `in section, of the spreader shown in FIG. 8;

FIG. 10 isa top view of `a tucker utilized in the mechanism of FIG. 1;

FIG. l1 is an enlarged cross-sectional view taken gen* -erally 4along line 11-11 of FIG. l and looking in the `direction of the arrows, but with the folders being fully open, anda carton being shown vin dashed lines;

FIG. l2 is an enlarged fragmentary schematic plan view of the front folder cams;

FIG. 13 is an enlarged fragmentary schematic plan view `of the rear folder cams;

FIG. 14 is an enlarged fragmentary top plan view of one set of two opposed pairs of folders of the machine of FIG. 1, with a carton shown in dashed lines;

FIG. 15 is a right end view of FIG. 14;

FIG. 16 is a left end view of FIG. 14;

FIG. 17 is a side'elevation view of the mechanism of FIG. 14;

FIG. 18 is a perspective view of a folder, and FIG. 19 is a perspective view of a tubular carton blank for forming a carton having bellows-type gussets at the V.corners to define an octagonal enclosure.

The mechanism illustrated in the attached drawings comprises an embodiment of this invention particularly adapted for forming gussets at each corner of erected, rectangular tubular carton blanks C as in FIG. 19. Re-

ferring particularly to FIG. 19, and the left-end carton in FIG. 1 as examples, each blank C is a set-up, glued tubular blank including a top wall 24, bottom wall 26, and side walls 28 and 30. A bellows-fold gusset construction is provided at each corner of the blank with each Vgusset comprising a ap portion 28a or 30a foldably connected to the `respective side wall, and adjacent triangular sections 24arand 26a, each joined along one side to the respective ap portion by a foldline 32 and joined along a second side to the top and Abottom walls by diagonal foldlines 34. Suitable end closure flaps 24h, 26h, 28b, and 30b are foldably connected to the ends of the top and bottom walls and to the flap portions.

AIn ,forming a carton from a blank C, each gusset iiap 28a and 30a is folded inwardly to the position shown in FIGS.`4 and 7. Each triangular section 24a and 26a is thus folded inward, about the respective foldlines 32 and 34 .to a `reversed position in back-to-back relation to the respective wal124 or 26 and provides lateral support for the gusset aps. Assumingeach foldline 34 defines an angle of approximately 221/2 with the respective foldvline 32, each folded gusset will extend inwardly at an angle of 45 to the respective side wall 28 or 3G. There- Y upon, closing of the end closure flaps completes a carton withan octagonal enclosure, see FIG. 4.

The` operation of the illustrated mechanism in forming an erected carton from blanks C will rst be outlined withreference to FIG. 1. This ligure illustrates a section -of a carton erecting and closing machine 36 wherein a .bellows-foldgusset 28a or 30a is folded inwardly at each corner of erected, or squared-up, rectangular, tubular blancks C to form an octagonal enclosure in each completed carton, see FIG. 4. The carton blanks move through the machine in uniform ,continuous movement from left to right in FIG. l, each blank C being placed on conveyor chains 38, by any suitable means (not shown), and supported in erected tubular form by a set of folders 40a, 40h, 42a .and 42h, see also FIG. 14. rThe tubular blanks are disposed transversely of `their path of movement through the machine 36, i.e., with their open ends on opposite sides of chains 38 and the closure flaps 2411 and 26,5 extending generally parallel to the path of carton movement as illustrated. As the carton blanks proceed through the machine 36, spreaders 44a and 44b enter the opposite open ends of each carton to spread the respective end portions of top and bottom walls 24 and 26. The folders 40a, 40b, 42a and 42b then fold the gusset iiaps 28a and 30a partially inward, the spreaders 44a and 44!) retract, and the folders complete their inward folding movement. Y-shaped tuckers 46a and 46h then move inward against the upper portions of the respective gussets 28a and 30a to insure proper cornpletion of the gusset folds. The end portions of the resulting, partially completed cartons pass between presser bars 48a and 4811 which retain the gusset folds as the cartons move into and through end closing mechanism (not shown, except for plows 50) of any type suitable for closing and securing the end aps 24h, 26b, 28h and ab to complete the cartons.

The conveyor chains 38 are supported on a pair of bed members 51 (FIG. ll) which maintain the chains and hence the folders and carton blanks on a fixed path as they traverse machine 36. The bed members as well as the various operative .components of the `machine are supported on a suitable framework indicated generally y by the numeral 56. Secured to the chains 38 at regular intervals are sets of folders, each such set comprising a pair of `folders 40a and 4% pivotally mounted on a support plate 52 and a pair of opposing folders 42a and 42h pivotally mounted on a support plate 54. Plates 52 and 54 are secured to and carried by the chains 38 at an appropriate spacing whereby folders 42 are spaced from the respective opposed folders 40 a distance corresponding to the Width of the carton blanks to be folded. The spacing between sets, i.e., between the folders 42 f of one set and the folders 40 of the next adjacent set,

and the drive to chains 38, are appropriate to effect proper timing for engagement of each blank in succession by the spreaders and tuckers.

The four folders 40a, 40b, and 42h are nearly identical in construction. Referring particularly to FIGS. 14-18, and using folder 46a (FIG. 18) as an example, each folder includes a generally L-shaped body block 601 comprising a short section 62 and a long section 64. The block 60 is pivotally mounted on a cap screw 66 (FIG. 14) which extends longitudinally through the short portion 6.2 of the block and is screwed into an ear portion 68 of support plate S2 (FIG. 16). A cam-follower roller '70' is carried on a shaft 72 extending from the end of the section 64 as shown. A pin 74 extends from the rear side of section 64, and is engaged by a tension spring 76 (FIG. 14) secured at its other end to a pin 78 secured to plate 52. A folder plate 80a is xed to the forward side of section `62 and extends outward of block 60, with respect to chains 38. An L-shaped member 82a is adjustably mounted on the outward side of section 64 of each folder 42]) by a cap screw 89. Each member 82a includes an elongated, body portion 84 formed with a slot 86, a laterally extending section 88, and a nger 90 which extends forwardly of block 60, toward the respective opposing folder 42a of the set, with its distal end directly above plate 80a, see FIG. 14.

Each folder includes the same component parts as outlined above for folder 40a with those variations rendered necessary by the specific position of each folder. Folder 4% diffe-rs from folder 40a in the direction of extension of the folder plate 80h, and the member 82b is a lefhand or mirror-image version of the member 82a on folder 40a. Folders 42a and 42h differ from 40u and 4Gb in that the body blocks 6) are inverted and are .mounted with the shoulder comprising the end of section 62 resting on ear portions of plate 54- (not shown, but corresponding to ears 68), with corresponding members 82a and 82!) extending upward, i.e., reversed with respect to the bodies 69, see FIGS. 15, 16- and 17. The folder plates 8i) of each pair of folders 40 and 42 are aligned with one another and with stop blocks 92 on support plates S2 and 54, as in FIG. 14, when the folders are in their retracted positions with sections 64 abutting stop pads 94 under the force of springs 76.

Folder plates 80a and 801) are of a depth slightly less than the minimum depth of cartons to be folded, and of a length corresponding to 4or somewhat shorter than the length of the gusset flaps to be folded on such cartons. Each folder plate extends across the center portion of the respective section 62, to be disposed in the same relative vertical position, just above the lower carton wall 26, whether the block 60 is mounted as part of a folder 40 or inverted in a folder 42. The members 82a and 82h are readily adjustable on cap screws 89 and are positioned so that the fingers 90 will each engage the respective gusset just beneath the upper edge, along folding score 32. These fingers assist in the iti-folding of the gussets. The adjustability of members 82 is one feature which facilitates quick and simple adaptation of the machine 36 for use with cartons of various depths.

Referring now to FIGS. 8 and 9, each spreader 44 includes a base member 96 adjustably mounted on a support bar 98 by a cap screw 160* for adjustment longitudinally of this bar. A spreader guide 102 is fixed to base member 96 and includes a step portion 104 With a distal end section 106 extending downwardly and rearwardly, beneath the step section 104, at an angle less than 90 to the plane of the base member 96. A bifurcated plate 168, including a base 110 and a pair of spaced fingers 112, is freely hinged along base 110 on a hinge rod 114 journalcd on base member 96. An upstanding stud 116 is secured to the center of base 110 and carries an operating roller 118 at its upper end.

Referring now to FIGS. 1, 3, 5 and 6, each spreader 44 is mounted with bar 98 secured on the ends of a pair of parallel arms 120' and 122 driven in parallel synchronism by a pair of drive sprockets 124 and 126 driven in synchronism as by a roller chain 128. Each spreader 44 is disposed with its longitudinal axis transverse to the direction of carton travel through the machine 36. It will be appreciated that as sprockets 124 and 126 rotate arms 120 and 122, the spreaders will maintain their orientation, extending laterally or transversely of the conveyor chain 38 as they are moved in a circular path. The spreaders are positioned to enter opposite ends of carton blanks C supported by the sets of folders on chains 38, between the top wall 24 and the bottom wall 26 of the blanks, and more particularly to extend between the respective end fiaps 24h and 26h and between the adjacent end portions ofwalls 24 and 26 during their inward movement, see FIG. 11.

A curved cam bar 130 is supported on adjustable brackets 132 at each side of machine 36 and positioned to be engaged by the roller 118 of the respective spreader 44 as the spreaders near the end of their inward movement, and thereby to pivot the respective plates 108 to their open position, see FIGS. 9 and 11. The curved bars 130 conform generally to the inner segment of the arcu- 4ate path of rollers 118 to retain plates 108 in their open position during movement of the spreaders through the forward portion of their respective arcs, i.e., those portions substantially parallel to the direction of movement of carton C through machine 36.

Referring now to FIG. 10, each tucker 46 comprises a Y-shaped tucker bar 134, including a pair of angularly disposed arms 135, extending from a slotted plate 136 which is adjustably secured to a support bar 138. A protruding gusset-engagement element 139 may be provided on the distal end portion of each arm 135 as illustrated. Referring now also to FIGS. 1, 3, 5 and 6, bar 138 is mounted on parallel arms 140' and 142, secured to sprockets 144 and 146 driven in synchronism, as by a roller chain 147, in the same manner as the corresponding support arms of the spreaders.

The spreaders and tuckers are driven in appropriate timed relation to the movement of chains 38 by direct drive mechanism driving shaft 148 which is drive-connected to gear 146 of the tucker drive. The spreaders are driven by a roller chain 150 engaging sprockets 151 and 152 keyed to shafts which are also keyed to sprockets 124 and 144, respectively.

Presser bars 154 (see FIGS. 1, 2, 3 and 11) are adjustably supported on the machine frame, above chains 38, by plates 156 and adjustable support rods 158. Bars 154 are positioned vertically in accordance with the thickness or depth of the blanks C to maintain the erected tubular blanks firmly in place on chains 38, between the folders, during transit of the blanks through the spreader and tucker operation.

Cams for operating the folders are illustrated somewhat schematically in FIGS. 12 and 13. Two top `cams 161m and 161111, for operating the front folders 40, are disposed in the paths of the rollers 70 of folders 40a and 40h to be engaged by these rollers as the folders are carried through machine 36 on chains 38. Each of these cams includes a first rise portion 162 to pivot the respective folder plate 8f) to its partially closed position, and a dwell portion 164 to maintain this position, a second rise 166, a notch 168 (for purposes to be later described), and a final dwell portion 170 to maintain the respectivo folder plate in its fully in-folded position. Lower cams 1'72a and 1721) are also oppositely disposed, and are positioned to engage the operating rollers 70 of the folders 42a and 42b. Each of the latter cams includes Aa rise portion 174, partial-fold dwell portion 176, rise portion 178 to effect full in-folding of the gussets, and a final dwell portion 180. Cams 1605 and b are suitably supported in the paths of the respective rollers 70, as by a plate 182 and rods 184 and 186 secured to the frame of machine 36, see FIGS. 3 and 11. Cams 172a and 1721) are secured to bed members 51 and are disposed with their leading ends spaced from the leading ends of cams 160a and 16%, longitudinally of machine 36, a distance approximately equal to the spacing of folders 4@ from folders 42 whereby the drive rollers 7) of a set of folders will engage the respective cams to effect folding of all four gussets of a blank C at substantially the same time.

The vertical positioning of the spreaders and tuckers may be varied to effect alignment with carton blanks of dif ferent depths, as by varying the configuration of the support elements, such as plates 96 and 136 and bars 98 and 138. Tuckers 46 may be omitted when the machine is used with blanks of a depth corresponding closely to (but slightly greater than) the depth of the folder plates 80. The spreaders and tuckers are adjustable laterally of chains 38, on their support bars 98 and 138, to accommodate carton blanks of various lengths, and the arcuate cam bars 130 may be :adjusted on brackets 132 accordingly and to effect the desired amount of opening movement by plates 168.

It is believed that the operation of the aforcdescribed mechanism, as well as the novel method which it is adaptedto perform, is clear from the foregoing outline of the operation and detailed description of the operative elements of machine 36. However, a further specific detailed description of the operation is set forth hereinafter for clarity.

A squared-up carton blank C is positioned on chain 38 between folders 40 and 42 of a set, either by hand or by s-uitable mechanism, for instance by automatic feedforming hopper, or by other suitable mechanism in a packaging system. The product is normally positioned within the squared-up blank prior to placement of the blank between the folders but may be inserted in the erected blank while on the conveyor chains. As chains 38 are driven, the respective folders engaging a blank C are moved through the machine 36, see FIG. l. As the blank proceeds through the machine the spreaders 44 are moved forward on larms 120 and 122 (FIG. 3) and enter the a' respective ends of the tubular blank with the hinged plate 108 closed as-in FIG. 5. Each inclined end section M6 engages the respective end flap 26b and end portion of the lower wall 26 as roller 118 engages the respective cam bar 13d to pivot plate 198 to the open position, thereby spreading the ends of the respective tubular blank C, see FlGS. 6 and l1. The spreaders remain open and within the ends of the carton blank, and move generally synchronously with the carton as the operating rollers 70 of the front folders 4t) and rear folders 42 engage the rst lrise portions 162 and 174 of the respective cams 160 and 172 to pivot the folder plates Si) and hence the ,gussets 28a and 30a to a partially closed position. This starts the movement of the gussets between the spread end portions of the top and bottom Wall. The operating rollers 70 then engage dwell portions 164 and i'l'o to maintain the partially folded position of folder plates titl as the spreaders retract. Continued movement of the folders and carton through machine 36 results in engagement of the rollers 70 of folders 42 on rise portions 78 of the lower cams to complete the closing of the rear kgussets as the tuckers 46 start forward. At substantially the same time, or slightly after this infolding of the rear folders, the operating rollers 70 of the front folders engage the second rise portions 166 of the top cams to continue the infolding of the front pair of gussets. The upper rollers 70 engage notches 168 as the spaced fingers 135 of the `tuckers 46 engage the respective gussets at their upper portions, adjacent the fold lines 32. Notches 163 thus result in momentary release of the blank C by the folders to allow for self-readjustment of the blank C due to any misalignment or distortion which may have been incurred during the folding steps thus far performed. The tuckers 46 continue moving to their inward end-positions (see FIG. ),y and move generally synchronously with the movement of blank C by chains 38 las the front folder rollers 70 move out of notches 168 to pivot folders 40 to their fully in-folded position. At this point, top and bottom walls 24 and 26 with attached closure flaps Zlb yand `2811 have substantially returned to their parallel planar positions. The tuckers 46 then retract, and folders 40 and 42 maintain the gussets in their fully closed position, due to continued engagement of rollers 7d with dwell portions 170 and 180 of the respective cams, as the carton blank passes between the presser bars 48a and 48b (FIGS. 6 and 7). The bars 48a and 48b press the end portions of walls 24 and 26 together to maintain the completed bellows fold of the gussets and retain the blank C in the resulting folded condition with the end closure flaps protruding as in FIG. 7. Thereafter, the closure aps 24b and 24b may be closed and secured in any suitable manner to complete and retain the carton in final erected condition as illustrated in part in FiG. 4. This final closing and securing may be performed by conventionalmachines in accordance with the type of end closure desired and the type of flaps provided. This may be by use of an overwrap, glued flaps, binding materials, locking tabs, or other known means.

The apparatus embodying the present invention may be conveniently integrated with conventional carton end closure apparatus by extending the runs of chain 38 through such end closure means, or by passing the blanks C onto another conveyor, while maintaining the end portions of walls 24 and 26 under compression to retain the gusset folds, for instance by extending presser bars 48a and 48b. By way of illustration, in the machine 36, these presser bars extend between a set of plows 50 which begin the closing of flaps 24b and 26b of blank C.

The method of the present invention is deemed apparent from the foregoing. In summary, this comprises supporting the erected blank C in squared-up condition, inserting the spreaders into the open ends of the blanks and actuating the spreaders to spread the ends of walls 24 and 26 and support the walls in this spread position to prevent their collapse towards one another as the gussets are folded inwardly, then partially folding the gussets, between walis 24 and 26, withdrawing the spreaders, and completing the folding movement of the gussets. The gussets at one side of the carton are released momentarily, as the gussets are engaged and pressed inwardly near their upper edges by supplemental folding mechanism to insure uniform and complete folding of the gussets to the final in-folded position. The ends of the side walls are then pressed towards one another to retain the carton in the resultant partially erected form, with the gusset folds completed, and the gusset folds are permanently retained by subsequently securing the top and bottom walls in position, as by closing and securing the end closure flaps of the blank C.

It will thus be seen that improved methods and machines have been provided for forming cartons having bellows-type, infolded gussets at the corners. Improved spreader means have been provided for positively and rapidly engaging and spreading the carton ends in a manner well suited to high-speed, automatic cartoning machines, including machines providing continuous movement of the carton blanks. Also, improved folders have beenprovided which are of a flexible design, being reversivarious depths simply by adjusting the lingers S2. Further,

the other manipulative elements of the disclosed machines are also readily adaptable to carton blanks of various dimensions and configurations, thereby conveniently providing a high degree of flexibility of the machines.

While a particular embodiment of this invention is illustrated and described herein, it will be understood, of course, that the invention is not limited thereto since modilications may be made by those skilled in the art, particularly in light of the aforedescribed teachings. Therefore, it is contemplated by the appended claims to cover any such modifications as fall within the true spirit and scope of the invention.

I claim:

1. A method of forming a carton from a tubularblank having gussets at the corners thereof capable of being folded inwardly between opposed Walls of the blank, said method comprising squaring-up'such tubular blank whereby said opposed walls thereof are in spaced substantially registered relation and at least one end of the blank is open, spreading apart said walls of said blank at said one end, partially folding the gussets inwardly between said spread walls of said squared-up blank, releasing said Walls, completing the inward folding movement of the gussets, pressing said walls toward one another at said one end to maintain such gussets in their final infolded position and securing said walls of said blank.

2. A method of forming a carton from a tubular blank having gussets at the corners vthereof capable of being folded inwardly between opposed walls of the blank, said method comprising squaring-up such tubular blank whereby .said opposed walls thereof are in spaced substantially registered relation and at least one end of the blank is open, spreading apart said walls of said blank adjacent the corners thereof at said one end, pressing inwardly on the portions of said gussets adjacent one of said opposed walls to partially fold the gussets inwardly between the spread walls of said squared-up blank, releasing said walls, continuing the inward folding movement of such gussets, momentarily releasing such gussets from pressure on said portions and substantially simultaneously pressing inwardly on such gussets adjacent the other of said opposed walls, pressing said opposed walls toward one another at said one end to maintain such gussets in their nal infolded position and securing such top and bottom of said blank.

3. A machine adapted for folding gussets in a tubular carton blank having gussets at one end to Ibe folded between opposite sides thereof comprising means to support such blank in erected tubularform, a spreader movable generally axially of such erected blank to a position between such opposite sides of such blank and operable to spread such opposite sides adjacent said end thereof, and folder means for folding such gussets between the sides of said -blank and operative to effect auch folding while said sides are spread by said spreader.

4. A machine adapted for folding gussets in a tubular carton blank having gussets at one end to be folded between opposite sides thereof, comprising a conveyor for supporting and moving such a tubular blank in a rst direction with said one end extending laterally of said direction of movement, a spreader disposed at a station of travel of the conveyed blank and being movable transversely of said first direction into such tubular blank to a position -between such opposite sides of such blank and operable to spread such opposite sides adjacent said one end thereof, and second means operative at said station for folding the gussets between the spread sides of the blank.

5. A machine as in claim 4 wherein said spreader is movable generally synchronously with such blank in said first direction of movement during spreading of such opposite sides.

6. A machine adapted for folding gussets in a tubular carton blank having gussets at one end to be folded between opposite sides thereof, comprising a conveyor for supporting and moving such blank in a first direction with said one end extending laterally of said direction of movement, a spreader disposed at a station of travel of the conveyed blank and being movable between such opposite sides of the blank and operable to spread such opposite sides adjacent said one end thereof, folders carried by said conveyor for folding the blank gussets inward between the spreader-engaged opposite sides of such blank, and means for pressing such opposite sides toward one another after release of such sides by said spreader and prior to retraction of said folders.

7. A machine adapted for folding gussets in a tubular carton blank having gussets at one end to be folded between opposite sides thereof, comprising a conveyor for supporting and moving such blank in a first direction, a spreader at a station of travel of the conveyed blank, said spreader being movable transversely of said first direction into such tubular blank to a position between opposite sides of the blank and operable when so extended to spread such opposite sides adjacent said one end of such blank while such blank is being moved by said conveyor, and folding means carried by said conveyor and operative subsequent to spreading of such sides for folding the gussets inward between such spread sides as such blank is moved by said conveyor.

8. A machine as in claim 7 and including further means disposed adjacent said conveyor for engaging and pressing inward on gussets folded inward by said folding means, to assist in folding the gussets.

9. A- machine adapted for folding gussets in a tubular carton blank having gussets at one end to be folded between opposite sides thereof, comprising a conveyor for supporting and moving such blank in a rst direction with said one end extending laterally of said direction of movement, a spreader at a station of travel of the conveyed blank, said spreader being movable along an orbital path for movement laterally of said first direction to a position between opposite sides of the blank and for movement generally synchronously with such blank while so positioned, said spreader being operable when so positioned to spread such opposite sides adjacent said one end of such blank while such blank is being moved by said conveyor, folding means carried by said conveyor and operative subsequent to spreading of such sides by said spreader for folding such gussets inward between such spread sides as such blank is moved by said conveyor, and presser ngers disposed adjacent said conveyor and movable along an orbital 4path for engaging and pressing inward on gussets folded inward by said folding means,

to assist in folding the gussets, said presser fingers being movable generally synchronously with such blank during such engagement.

10. A machine for folding gussets of a tubular carton blank having gussets at the corners thereof capable of being folded inwardly between top and bottom walls of the blank, comprising a conveyor for supporting and moving such blank in a first direction, a spreader at a station of travel of the conveyed blank, said spreader being movable between opposite sides of the blank and operable to spread such opposite sides adjacent one end of such blank while such blank is being moved by said conveyor, first means carried by said conveyor and operative subsequent to spreading of such sides for folding the gussets inward between such spread sides as such blank is moved by said conveyor, further means disposed adjacent said conveyor for engaging and pressing inward on gussets folded inward by said irst means to assist in folding the gussets, and wherein said first means engage the gussets adjacent one of said walls and said further means engages said gussets adjacent the other of said walls.

11. A machine for folding gussets in carton blanks each having a gusset flap in one side wall thereof with bellows panels in spaced opposed walls and foldably joined to said gusset flap, comprising means for folding such gusset inward between such opposing walls, a spreader movable between such opposed walls for insuring spreading of such walls relative to one another as such gusset is folded inward therebetween, and further means for engaging and pressing inward on gussets folded inward by said first means to assist in folding the gussets.

12. A machine for folding gussets in four corners of a tubular carton blank provided with a gusset iiap in a side wall at each such corner thereof and bellows panels in opposing top and bottom Walls foldably joined to each such gusset flap, comprising two opposed pairs of pivotally mounted folders adapted for supporting such a blank erected therebetween, a spreader movable between such top and bottom walls at each end of said blank, means for operating said spreaders when disposed between such walls to spread such opposing top and bottom walls adjacent such gussets, means for pivoting said folders to fold such gussets between such spread sides, to rnomentarily release said folders, and then to return said folders in their infolded position, further means for engaging and retaining such gussets during such release of said folders, and means for pressing such top and bottom walls toward one another to retain such gussets in their inwardly folded positions.

13. A machine for folding gussets in four corne-rs of a tubular carton blank provided with a gusset ap in a side wall at such corner thereof and bellows panels in opposing top and bottom walls foldably joined to each such gusset flap, comprising two opposed pairs of pivotally mounted folders adapted for supporting such a blank erected therebetween, each of said folders including a folder plate and a folding member movable with said plate and adjustable relative to said plate for engaging and folding panels of various widths, a spreader movable between such top and bottom walls at each end of said blank, means for operating said spreaders when disposed between such walls to spread such opposing to-p and bottom walls adjacent such gussets, means for pivoting said folders to fold such gussets between such spread sides, and means for pressing such top and bottom walls toward one another to retain such gussets in their inwardly folded position.

14. In a carton erecting machine, a folder comprising a pivotally mounted body including a folder plate for engaging and folding a panel of a carton blank, and a folding member movable with said plate and having a panel engaging portion spaced from said plate and in substantially the same plane as said plate to engage a panel engaged by said plate, said folder member being 1 l l E adjustable .relative to said plate to vary the spacing of long leg portion, said short leg portion being adapted for said portion from said plate While maintaining such planar pivotal mounting at either end thereof. relationship therebetween, whereby said `folder is adapted to engage opposite edge portions of panels of Various References Cited WltshS-A .f 1d f t t hi 5 UNITED STATES PATENTS .i o er or use 1n car on erec ing mac nes corn- 2,866,393 12/1958 Kemp 93-49 pnsmg a generally L shaped body having one long leg 3,016,807 H1962 Kerr 53 374 X por-tion and a parallel short leg portion, a folder yplate secured to said short leg portion mid-way between the BERNARD STICKNEY Primary Examiner ends thereof, and folder operating means secured to said 10 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,354,797 November 28, 1967 Robert J. Hickn It is hereby certified that error appears in the above numbered patent requiring correction and that the Said Letters Patent should read as corrected below.

Column 4, line 39, after "4Gb," insert 42a line 66 for "1ef" read leftcolumn 7, line 50, for "24h", second occurrence, read 26h column 8, line 25, for "rapidly" read readily column 10, line S3, after "at" insert each Signed and sealed this 7th day of January 1969.

(SEAL) Attest:

Edward M. Fletcher, Jr. EDWARD I. BRENNER Attesting Officer Commissioner of Patents 

1. A METHOD OF FORMING A CARTON FROM A TUBULAR BLANK HAVING GUSSETS AT THE CORNERS THEREOF CAPABLE OF BEING FOLED INWARDLY BETWEEN OPPOSED WALLS OF THE BLANK, SAID METHOD COMPRISING SQUARING-UP SUCH TUBULAR BLANK WHEREBY SAID OPPOSED WALLS THEREOF ARE IN SPACED SUBSTANTIALLY REGISTERED RELATION AND AT LEAST ONE END OF THE BLANK IS OPEN, SPREADING APART SAID WALLS OF SAID BLANK AT SAID ONE END, PARTIALLY FOLDING THE GUSSETS INWARDLY BETWEEN SAID SPREAD WALLS OF SAID SQUARED-UP BLANK, RELEASING SAID WALLS, COMPLETING THE INWARD FOLDING MOVEMENT OF THE GUSSETS, PRESSING SAID WALLS TOWARD ONE ANOTHER AT SAID ONE END TO MAINTAIN SUCH GUSSETS IN THEIR FINAL INFOLDED POSITION AND SECURING SAID WALLS OF SAID BLANK. 